Therefore equipment no longer required. That is it I'm afraid.
But this is not the full story. A runway is "no longer required" if an airport tells all its airline customers to go away. A terminal is "no longer required" if an airport tells its passengers to go away.
MAG apparently switch-sells MAN's whole-plane cargo leads to EMA and STN. And if they don't go there they're likely to be told they can't come to MAN anyway.
There IS proven demand for whole-plane cargo at MAN. For example, do you recall when CargoLogicAir announced plans to base a B747 freighter at MAN (but then the base "mysteriously" materialised at STN instead)? The airport has to accept the business in order for the support equipment to be required. That is where the real shortfall is, and it isn't good enough. 'The airport which likes to say NO' is saying ...
Earlier this year, THG indicated that they intended to set up a cargo airline at MAN but all has gone quiet with them. Not sure what is happening there. But their products certainly need to reach global markets. As do those associated with many other NW importers / exporters. This is still a manufacturing region.